In connection with the use of, for example, paint spray guns, compressed air or gas is normally used as a propellant for atomizing and discharging paint material from the paint spray gun. It is known, however, that compressed air or gas produced by means of conventional compressor apparatus normally has a relative humidity value that may be within the range of, for example, 50-100%. When the compressed air or gas is characterized by means of such a relatively high level of relative humidity, there is a relatively high likelihood that moisture or water vapor condensation will occur or be present within the various operational components comprising the compressed air or gas feed system, such as, for example, the various compressed air or gas lines, the compressed air or gas line fittings, the compressed air or gas regulation devices, or the like. In any case, it is desirable to lower the relative humidity values of the compressed air or gas by effectively removing the moisture content from, or reducing the moisture content within, the incoming compressed air or gas so that water vapor condensation does not in fact occur. This is particularly desirable in connection with the use of paint spray guns because otherwise, the moisture or water vapor condensation will be entrained within the sprayed paint thereby rendering the paint material composition unacceptable from the viewpoint of its desired, intended, or required specifications.
In order to achieve the aforenoted elimination or reduction in the relative humidity or moisture content within the incoming compressed air or gas, air or gas drying systems comprising, for example, refrigerated, adsorbent, or absorbent type dryer mechanisms, are conventionally employed in connection with the source of the compressed air or gas. Such systems are quite effective and are even capable of drying compressed air or gas to below-zero dew point levels. However, notwithstanding the use of such drying systems, there is no guarantee that the compressed air or gas being conveyed through the system will have the requisite relative humidity values, levels, or characteristics at the actual end point of use, that is, at the inlet to the paint spray gun where the incoming compressed air or gas will now mix with and entrain the paint material within the fluid stream. Therefore, not only can moisture or water condensation be present or occur within any one or more of the aforenoted various operational components comprising the compressed air or gas feed system, such as, for example, the various compressed air or gas lines, the compressed air or gas line fittings, the compressed air or gas regulation devices, or the like, but in addition, at any point in time, the drying system may lose some of its effectiveness or efficiency due to, for example, a malfunction, the exhaustion or depletion of its treatment materials, or the like.
Still yet further, even if the drying system is working satisfactorily or optimally, moisture or water vapor, derived or originating from other sources, may nevertheless become entrained or entrapped within the operational compressed air or gas infeed system and may present themselves during the actual paint spraying process or operation. For example, during a particular paint spraying application, the lengthy compressed air or gas lines or hoses may need to be disconnected, exchanged, replaced, reconnected, or the like. Each time one of the hoses or lines is in fact disconnected and subsequently reconnected, unwanted and undesirable moisture-laden ambient air can or will be admitted into the system and will therefore be conveyed through the system, mixing with the paint material being entrained thereby, until it is ultimately exhausted or discharged from the paint spray gun and eventually replaced with treated compressed air or gas coming from the compressed air or gas source. As has been noted hereinbefore, moisture or water vapor condensation entrained within the sprayed paint is unwanted and undesirable in that the same renders the paint material composition unacceptable from the viewpoint of its desired, intended, or required specifications. Under such circumstances, and in accordance with any one of the foregoing modes of operation, that is, whether the air or gas drying system is not working optimally, or just as a result of the inherent operational or structural characteristics of the overall system, operator personnel may not even realize that such contaminated sprayed paint is in fact being discharged from the paint spray gun in view of the fact that the operator may be operating, in effect, under a false sense of security in that the source of the compressed air or gas does have the air or gas drying systems operatively associated therewith. Continuing still further, it is also important, in connection with the use of paint spray guns, that the pressure of the incoming compressed air or gas be regulated and monitored so as to ensure that the pressure is in fact at a desired or specified value. The pressure level of the incoming compressed air or gas is important because the amount of paint entrained within the compressed air or gas stream is a function of the pressure level of the compressed air or gas. Accordingly, depending upon the pressure level of the compressed air or gas, the color of the paint expelled or discharged from the paint spray gun and applied onto the particular substrate can vary. Therefore, it is imperative that for a particular spray paint application, the pressure of the incoming compressed air or gas must be maintained at a predetermined value.
Continuing further, then, while pressure gauges have in fact been utilized in conjunction with paint spray guns for measuring and monitoring the pressure level of the incoming compressed air or gas, as exemplified by means of U.S. Pat. No. 5,191,797 which was issued to Smith on Mar. 9, 1993, as well as United States Patent Application Publication 2003/0230636 which was published in the name of Rogers on Dec. 18, 2003, and while a dryness indicator is also disclosed within United States Patent Application Publication 2005/0199403 which was published in the name of Arno et al. on Sep. 15, 2005, to date there is no single piece of equipment or apparatus which effectively comprises a composite or combination pressure gauge and relative humidity indicator which can conveniently and readily be utilized in conjunction with a paint spray gun in order to provide the operator with current or up-to-date accurate or precise pressure and relative humidity readings, values, or levels so that the operator can in fact continuously monitor the pressure and relative humidity levels of the incoming compressed air or gas whereby necessary corrective steps or action can be taken, such as, for example, the altering or adjusting of the pressure level of the incoming compressed air or gas, or the temporary stoppage of the operation of the paint spray gun while the operation of the drying system is checked. In this manner, the proper operation of the paint spray gun can be ensured to the effect that the paint being sprayed by means of the paint spray gun is precisely controlled from the viewpoints of paint color, paint consistency, and the like.
In addition, it is also noted that the aforenoted pressure gauges and dryness indicator components are integrally incorporated upon or within the handle structure or housing of the paint spray gun. This is not particularly desirable from an operational point of view because if the pressure and dryness of the incoming compressed air or gas is desired to be measured, monitored, and controlled in connection with a paint spraying operation, only those tools or paint spray guns, which are equipped with the pressure gauges or dryness indicator of the types disclosed within the aforenoted patent publications, can be used. Viewed from a different perspective, if a particular user, whether an individual, already having one or more paint spray guns which are not equipped with the pressure gauges or dryness indicator of the types disclosed within the aforenoted patent publications, or a business, having a multiplicity of paint spray guns which are likewise not equipped with the pressure gauges or dryness indicator of the types disclosed within the aforenoted patent publications, want to perform a paint spraying operation under precisely or accurately controlled pressure and dryness conditions in order to attain the desired paint deposition results in connection with color, consistency, and the like, they will not be able to do so because the pressure gauges or dryness indicator, as disclosed within the aforenoted patent publications, cannot be mounted or affixed upon existing paint spray guns. In order for the individual or company to reap the benefits of being able to measure and monitor the pressure level and dryness of the incoming compressed air or gas, they must therefore in fact purchase or use the particular paint spray guns disclosed within the aforenoted patent publications.
A need therefore exists in the art for a new and improved combination digital pressure gauge and relative humidity indicator which can readily be mounted or affixed upon any paint spray gun in order to provide the operator with immediate and accurate pressure and relative humidity readings, values, or levels so that the operator can in fact continuously monitor the pressure and relative humidity levels of the incoming compressed air or gas whereby necessary corrective steps or action can be taken, such as, for example, altering or adjusting the pressure level of the incoming compressed air or gas, or temporarily stopping the operation of the paint spray gun so that the operation of the drying system can be assessed or checked as to whether or not the drying system is operating properly, whether or not the drying system needs to be repaired or replaced, or the like. These remedial measures can be taken so as to ensure that the paint being discharged or sprayed is precisely controlled from the viewpoints of paint color, paint consistency, and the like.